26-08-2016, 09:09 PM
I've been wanting to try out some of Clive Sinclair's circuits for micro alloy transistors for quite a while - since about 1960-something, actually - so when I noticed that J Birkett was offering untested MATs at 5 for £1 I splurged and ordered 50. Yes, over the top, I know, but I figured this was a last-chance buy and you never know when you might need a few MATs.
Anyway, they arrived yesterday and this evening I thought I'd test a few. The good news: all those I tested seem to be OK. The bad news: they're not MATs! I noticed that they had Vbe of around 600 - 700 mV and I thought that can't be right for a germanium transistor. I then looked a bit more closely and saw that some were marked SA52B. A quick Internet search confirmed that this is a silicon small signal transistor - made by GEC Plessey/Semiconductors - and definitely not a microalloy germanium type.
I'm not really complaining about this - I'm sure John Birkett sold them in good faith and, to be fair, they are identical in appearance to "real" MATs - but I though it was worth mentioning here in case anyone else wanted some MATs and was thinking of ordering from John.
I'll drop John a note telling him about this - I don't think he does email!
In the meantime, if there's anyone out there who would like to swap a few really nice SA52B transistors for some real MATs, I'd be pleased to hear from them!
Anyway, they arrived yesterday and this evening I thought I'd test a few. The good news: all those I tested seem to be OK. The bad news: they're not MATs! I noticed that they had Vbe of around 600 - 700 mV and I thought that can't be right for a germanium transistor. I then looked a bit more closely and saw that some were marked SA52B. A quick Internet search confirmed that this is a silicon small signal transistor - made by GEC Plessey/Semiconductors - and definitely not a microalloy germanium type.
I'm not really complaining about this - I'm sure John Birkett sold them in good faith and, to be fair, they are identical in appearance to "real" MATs - but I though it was worth mentioning here in case anyone else wanted some MATs and was thinking of ordering from John.
I'll drop John a note telling him about this - I don't think he does email!
In the meantime, if there's anyone out there who would like to swap a few really nice SA52B transistors for some real MATs, I'd be pleased to hear from them!
